40.3 Other Endocrine Glands and Hormones -- Part 4
The tendency for type 2 diabetes to occur more often in certain families, or even ethnic groups is a result of complex genetic factors.
African Americans are more likely to have the condition than non-Hispanic whites.
Normally, when the binding of insulin to the plasma membrane receptor is done, there is an increase in the number of glucose carriers in the cell.
The number of glucose carriers does not increase in type 2 diabetes.
The cell is said to be resistant to the drug.
It is possible to prevent or at least control type 2 diabetes by following a low-fat, low-sugar diet and exercising.
If this fails, oral drugs can be used to increase the metabolism of sugar in the body.
The effects of type 2 diabetes are as serious as those of type 1 diabetes, even if millions of Americans don't know about it.
Both the exocrine and the endocrine parts of the pancreas are present.
The duodenum is where the juices are sent and the hormones are sent into the bloodstream.
In 1920, Frederick Banting tried to find a way to separate the drug from the chemical messenger.
He knew from previous research that the only cells that could be damaged by tying off the pancreatic duct were the ones that produce bile.
A graduate student, Charles Best, was assigned to assist his professor at the University of Toronto.
Banting and Best spent their summer working, sleeping, and eating in the lab with limited funds.
By the end of the summer, they had obtained extracts that lowered the blood sugar level in dogs.
Macleod brought in biochemists to purify the extract.
In 1922, the first human patient was treated withinsulin therapy and large-scale production of the drug from pigs and cattle followed.
Banting and Macleod received a prize for their work.
The sequence of the amino acid was determined in the 60's.
The required steps were performed by Banting and Best.
Some people don't like using animals for medical research.
Best and Sir Frederick Banting were the first to keep a dog alive by injecting it withinsulin.
The hypothalamus and pituitary control the activity of the testes and ovaries.
The testes are located in the scrotum.
The male sex hormones are produced by the testes.
The female sex hormones are produced by the ovaries.
The gonadotropinreleasing hormone is controlled by these hormones.
The sex hormones give feedback on the production of the folliclestimulating hormone and luteinizing hormone.
Chapter 41 talks about the activities of FSH and LH.
The growth of the penis and testes is stimulated by the increased amount of testosterone that the testes release at puberty.
The male secondary sex characteristics that develop during puberty are maintained by Testosterone.
The growth of facial, axillary, and pubic hair are included.
It causes the voice to lower because of the enlarged vocal cords.
Testosterone stimulates sweat and oil in the skin.
A side effect of testosterone is hair loss.
Male baldness is more common because of the presence of testosterone.
Some athletes take supplemental amounts of steroids because testosterone is a part of the muscular strength of males.
There are a number of body systems that may be affected by improper use of steroids.
There are many effects on the body of the female sex hormones.
Estradiol stimulates the growth of the uterus and vagina at puberty.
Female body hair and fat distribution are caused by estrogen, which is necessary for egg maturation.
Females have a more rounded appearance because they have more fat under their skin.
Monthly menstruation includes the discharge of blood and tissues from the uterus.
The development of muscle and bone strength, overall energy level, sex drive, and sexual pleasure are all caused by the small amount of testosterone produced by the ovaries and adrenal glands of women.
When daylight returns and melatonin levels are low, we grow sleepy at night, but when melatonin levels increase, we can wake up.
The internal timing mechanism called a biological clock controls the rhythms of the day.
At night, melatonin production is the best.
There is an opening in the skull that is covered by a thin layer of skin and the pineal glands on top of the brain.
The presence of light-sensitive cells in the pineal gland has led some investigators to conclude that it was a third eye at some point in evolution.
The exact functions of this structure are not completely understood, although it may have aided in determining the position of the sun.